This invention relates to the field of modular electronic assemblies and, more particularly, to quick disconnect terminals for electronically coupling wire leads to printed circuit (p.c.) boards.
With the advent of printed circuits, many attempts have been made to design quick disconnect terminals for printed circuit boards in which one or more wire leads are terminated in a quick disconnect terminal (usually a female terminal) which in turn leads to a corresponding terminal (usually a male terminal) which is affixed to the printed circuit board. However, many prior terminal designs have resulted in a substantial cost for the terminal which is connected to the printed circuit board or a substantial cost in preparing the printed circuit board to receive the quick disconnect terminal or in the assembly costs of affixing the terminal to the printed circuit board.
One such present quick disconnect male terminal is formed in the shape of an L such that the vertical portion of the L, which is perpendicular to the surface of the p.c. board, is used to mate with the standard female quick disconnect terminal connected to one or more wire leads. In this type of terminal, the horizontal portion of the L is affixed to the surface of the printed circuit board by means of an eyelet which is pushed through a hole in the printed circuit board from the opposite side of the printed circuit board and into a hole in the horizontal member of the L-shaped terminal. This eyelet is then peened over on the horizontal member of the L-shaped terminal securely affixing the quick disconnect terminal to the surface of the printed circuit board. This same L-shaped quick disconnect terminal could be equally affixed to the printed circuit board by means of rivets or bolts. Although these L-shaped quick disconnect terminals provide sufficient rigidity to allow the wire lead terminal to be disconnected from the printed circuit board L-shaped terminal without tearing the printed circuit board terminal from the printed circuit board, they have the disadvantages that the terminals themselves are expensive, affixing the terminal to the board is time consuming, and a relatively large amount of area on both sides of the printed circuit board is required for mounting the terminal. However, this L-shaped quick disconnect terminal does have the advantage that this method of affixing may be used on either male or female quick disconnect terminals.
Another quick disconnect terminal design, described more fully hereinafter, reduces many of these disadvantages. In this design, which is limited to male type quick disconnect terminals, an oblong hole is routed in the printed circuit board and the male terminal is inserted from the opposite side of the printed circuit board. In this male terminal design, the terminal blade has a spring clip punched in the lower portion of the terminal blade such that the spring retracts when the terminal is pushed through the printed circuit board and then springs into place locking the terminals such that it will not fall out of the hole in the printed circuit board. Further, the base of the terminal on the side of the printed circuit board opposite the blade is wider than the oblong hole, thereby retaining the terminal from falling out of the hole in the other direction. After this male terminal is inserted in the oblong hole in the printed circuit board, the terminal is then hand-soldered to the printed circuit board. Although the cost of the terminal itself is reduced by this design, and the area on the printed circuit board required for mounting this terminal is reduced, this design has the disadvantage that the routing of the oblong hole in the printed circuit board is more time consuming than simply drilling a circular hole and the hand-soldering of the terminal to the printed circuit board is a separate costly step. Routing has the further disadvantage that the routing tool will not last as long as a drill and secondly a routing operation does not permit multiple boards to be stacked and prepared simultaneously as is possible when only a circular hole is required to be drilled.
It is accordingly an object of the present invention to provide a quick disconnect terminal having a low per terminal cost and a low assembly cost. A further object is to provide a terminal which requires very little surface area on the printed circuit board for mounting but yet has the requisite rigidity and strength to withstand the pushing, pulling and the bending associated with connecting and disconnecting the mating wire lead terminal with the printed circuit board terminal. A still further object is to provide a quick disconnect terminal which may be retrofitted to existing printed circuit board designs without requiring a change in the artwork of the circuits on the board. It is still a further object to provide a quick disconnect terminal which can be wave-soldered to the printed circuit board.
This invention is pointed out with particularity in the appended claims. An understanding of the above and further objects and advantages of this invention may be obtained by referring to the following descriptions taken in conjunction with the drawings.